Facial sunspots (sun lentigos, or lentigines) are oval or round, pigmented spots that measure 2 to 20 mm, are brown, uniform, and located in areas frequently exposed to the sun, like the face, arms and back of the hands. They are larger than freckles/ephelides, do not disappear in the winter, and are common in ageing skin.
Solar lentigines are the result of the local growth of melanin-producing cells in response to ultraviolet radiation. These spots are more frequent among the Caucasian and Asian populations, and in women, especially after age 50. Although they are benign lesions that do not need medical treatment, they indicate that sun exposure has been excessive. For aesthetic reasons they can be eliminated by different treatments, although the best form of prevention is the use of sunscreens and limiting sun exposure.
Variations in MC1R and IRF4 genes have been associated with an increased risk of sunspots. There are numerous risk alleles in the MC1R (melanin receptor) gene.